Community Research and Development Information Service - CORDIS

Periodic Report Summary 2 - DNICAST (Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies)

Project Context and Objectives:
Concentrating solar technologies (CST) have proven to be very efficient sources of clean power for the electrical grid. The efficient operation of CST requires reliable forecasts of the incident irradiance for two main reasons:
- First, to allow for an optimal efficiency of the power plants.
- Second, the electricity production can be optimally connected to the grid.
The uncertainty in the forecast of the Direct Normal Irradiance (DNI) is still too large and must be reduced. The DNICast project brings a series of innovative components which will advance current state-of-the-art. These innovations can be clustered in terms of methodological progress, geographical extension and a participatory approach.

Methodological progress: In DNICast, methods based on information from a number of different sources such as ground measurements, all sky imagers, satellites and Numerical Weather Prediction (NWP) models will be used in an integrated way to offer more reliable DNI estimates for application in the field of CST. The mentioned methods have different time and spatial resolutions, and there is no single approach valid at all desired scales. Therefore a combination is needed. To validate several methods against references, accurate and reliable ground measurements of DNI and aerosol and cloud properties will be collected for sites located in the geographical areas of interest for the implementation of CST.

Geographical coverage: DNI nowcasting methods will be validated through ground measurements of DNI at different sites with high quality datasets. For the validation of the nowcasting methods metrics proposed by EU-funded and other international projects will be used. Another major innovation is to qualify data in relation with the instrument operators and to describe them with INSPIRE-compliant metadata. This effort will be twofold achieved:
- Firstly, a measurement grid at very high local spatial resolution in the area of 1 km² will be achieved. This will allow the validation of nowcasts with high spatial resolution as produced from all sky imagers.
- Secondly, a unique DNI database will be created for regions that are currently of interest for CSP plants, as the MENA region and the Arabian Peninsula.

Participatory approach: The DNICast consortium follows an integrative approach by bringing together specialists of different working fields. Leading institutions from the communities working on CST, ground based nowcasting and DNI measurements, satellite based nowcasts and NWP cooperate to obtain the best possible results. The direct contact with potential users of the nowcasting tools (e.g.: plant and grid operators) as well as with companies providing measurement and data services for the solar industry is also part of the consortium’s approach. Key research and industrial actors have provided letters of support to the project and will closely cooperate with the DNICast consortium through their involvement in the Project Advisory Board. Other stakeholders will be involved through a dedicated work package focusing on Knowledge Sharing and User Workshop, as well as through the project communication tools.

Project Results:
WP1-Project Management:

Administrative and operative management coordination activities proceeded in line with the Description of Work. OME coordinated the consortium efforts to guarantee smooth implementation of work and high quality of technical progress. Some of the activities performed within this framework are: Consortium Agreement (D1.1), Kick-off meeting and steering committee meeting (month 1) and 3 other project and steering committee meetings (months 9, 17 and 25), Advisory Board meetings (months 6, 17 and 25) and several bi-monthly teleconferences as well as the coordination of reporting.

WP2: Prerequisites for nowcasting method development

The objective of WP2.1 (completed in the first reporting period) is the definition of requirements of nowcasting methods for concentrating solar technologies which shall serve as a basis for the development of the nowcasting methods. The report covers both technologies: concentrating solar thermal and concentrating photovoltaic plants. Also requirements for the cloud description (e.g. cloud classification, extinction, velocity, height) and aerosol properties have to be defined. The specifications are summarized in a report (deliverable D2.1).

The objectives of WP2.2 and 2.3 are to provide the required aerosol input and information concerning circumsolar radiation for the nowcasting methods. Activities under this work package have ended. Cloud camera based AOD fields and a one year IASI/MODIS dataset were prepared. The bulk of the work on a report concerning SDS-WAS data was carried out within the first year of the project. Software to convert Aeronet AOD to clear sky DNI was developed. A list of input parameters for the calculation of circumsolar radiation had to be identified, so that the documented list could be distributed to the partners by the end of month 14.

WP3: Nowcasting method development

The overall objectives of WP3 are twofold: Objective 3.1 (O3.1) is to develop a variety of complementary methods for the nowcasting of DNI that cover different parts of the window from 1-240 min. Objective 3.2 (O3.2) is to combine these methods from O3.1 such that the complete nowcasting horizon is covered and the requirements from O2.1 are fulfilled.

In the first reporting period, the objective related to O3.1 was to prepare and install methods utilizing all-sky imagers in WP3.1 and numerical weather prediction models in WP3.3. Following the suggestion of the project’s advisory board, it was agreed on the progress meeting 2014 that the forecast horizon would be extended to 360 minutes.

Concerning work on nowcasting method development, an important element was the definition of the minimum spatial domain and time periods. Datasets are available for validation and combination. Innovative methods for using all-sky imagers to forecast very short term cloud variability have been developed. Existing methods for satellite-based cloud forecasting have been further developed. Numerical weather prediction (NWP) models to forecasting of DNI and circumsolar irradiances have been applied. NWP ensemble forecasting methods optimized for DNI forecasting have been developed.

WP4: Validation of the nowcasting methods and plant output nowcasting

The three objectives of WP4 are: To collect datasets of known and high quality; to validate nowcasted DNI provided by WP3; and to assess the influence of improvement in DNI nowcasting on nowcasting of CST plant output.
Regarding the validation of very short-term forecast and highly resolved local DNI forecast (DNI maps), the radiometric grid has been completed as planned and measurements, maintenance tasks are on-going. The operational version of the web platform designed for the dissemination of the quality-controlled measurements was launched in June 2015. Based on a selection of high-resolution measurements available, the validation of nowcasted DNI maps received from WP3 has started. As for activities related to validation of short-term DNI forecast, the collection and quality control of both the preliminary and final reference ground measurements have been completed, and preliminary NWP and satellite-based forecasts have been received. The development of validation algorithms for DNI at different sites is on-going. As far as CSP plant simulation and yield production nowcast, exemplary CST plants have been defined, with the collection of three CSP and four CPV plants. Preliminary example of hourly remuneration rates has been selected for the analysis of financial benefits of improved DNI nowcasting on CST plants operation.

WP5: Knowledge sharing and users workshops

The principal objective of this WP in the first year is to collect the expectations of the potential end users of the nowcasting methods. To do that two different actions have been held; on the one hand the first end-users workshop, in which the general project goals and methodologies have been exposed to the end users and on the other hand the bilateral consultations that try to collect all those technical aspects of the CSP plants that appears as critical to the development of the nowcasting methods. The goal of these consultations is to avoid that confidential issues do not allow that nowcasting methods developed in the DNICast cover all the potential end users requirements. During the second period, the second end-user workshop on “Application of Observations and Forecasts of Vertical Profiles of Aerosols in the Lowest 200 m of the Atmospheric Surface Boundary Layer in Optimizing Concentrated Solar Energy Power Plant Operations” was organized on December 2nd, 2016.

WP6-Communication and dissemination:

In terms of communication and dissemination, several dissemination and communication materials have been produced. A communication and dissemination strategy, including the design of the project logo, was developed already during the first reporting period and the deliverable (D6.1) is available on the project’s website. Regarding scientific dissemination, DNICast project members participated in several conferences/events and made presentations related to the project. Examples of events include: IEA SHC Task 46, Weather Intelligence for Renewable Energies WIRE Status Workshop, MACC–II Open Science Conference, 13th BSRN Scientific Review and Workshop, XI Congreso Iberoamericano y XXXVIII Semana Nacional de Energía Solar, 14th EMS Annual Meeting & 10th European Conference on Applied Climatology, ICEM Conference and SolarPaces, etc. Scientific publications in peer-reviewed journals have been also produced by the consortium partners, including Atmospheric Environment, Energy and Renewable Energy Journals.

Broader dissemination about the DNICast project was made through several tools: the development and continuous update of the project website (, the issuance of project newsletters, which have been distributed to a list of different stakeholders, and the development of the project leaflet, also produced during the first activity report. A first divulgative article on DNICast was produced during the first reporting period. A second one is currently being prepared and will be issued before the end of 2016 on the OME “GEM” magazine.

Potential Impact:
DNICast will contribute to the development of CST, thus increasing energy security, renewable energy supply, climate and environmental protection. Furthermore, through its integrated and participatory approach DNICast will enhance the current industrial and academic cooperation on innovation in energy technology, as foreseen by the EC Horizon 2020. Moreover, it will support the implementation of the Strategic Energy Technology (SET) plan, in particular by contributing to increasing the performance of CST and encouraging the commercial implementation of these technologies.

Improved and more reliable DNI estimations will increase the efficiency of CST plants, thus contributing to cost decrease and a massive deployment of renewable energy technologies, and will further strengthen the EU position in the field of CST. This will have important effects in terms of job creation, and other socio-economic benefits. In this respect, DNICast is fully in line with the EU research policy to develop an open and competitive European Research Area, which is a core element in the EC research and innovation agenda, and a specific objective of the Innovation Union Flagship initiative.

List of Websites:


Houda Ben Jannet Allal, (General Director)
Tel.: +33 169170120
Fax: +33 169170119
Record Number: 189237 / Last updated on: 2016-09-20